Transcript for Chris Hemsworth Reunites With Natalie Portman in 'Thor: The Dark World'

been sitting right there. One of the most anticipated films in the history of the medium. Hello, chris hemsworth. "Thor: The dark world." Right here, right now, the man who plays the norse god of thunder. Great to be with you. Thanks for having me. On a third go around with this character. You booted up the franchise. And avengers, you destroy this great city we're in now. But you're back for a third go. What do you like most now about a character you kind of know well now? Coming back the third time, you have a familiarity with the character. With the story. With each of the cast. And we didn't spend time getting to know one another. We just dove right into it. The action and drama. Taking it to the next level. And each time, we've been lucky enough to top that. I know you approached the character differently. Especially in the battle scenes. The thing does advance your skill set. A little more wire gags and special effects. So, he's upped the level of his battle skills. There's a self-awareness to him, as well. I want to show you a clip. Your brother, loki, you're asking him for help. Of course, that comes at quite a price. Take a look. We stood with each other in the past. I did so with a glimmer of hope that my brother was still in there somewhere. And hope no longer exists to protect you. You betray me, and I will kill you. When do we start? Perfect. You two light up the screen. It's great chemistry you have as actors. The two characters, a sibling dynamic rivalry here ramped up to a whole new level. I have brothers and tom has sisters. This is going to feel like when we were kids bickering. The issue is much larger than before, it's essentially the same thing. That love/hate disagreement. And plenty of others. And you were shooting "rush." You put -- we make a lot of actors putting on weight, taking off weight. But, boy, there is a real difference in the two. Look at this. There you are, norse god of thunder on the right. And then, a race car driver on the left. How is that? To get up and back down for two roles consecutive? Both are kind of extremes. "Thor" was lots of time in the gym. And that character was basically run every day and eat, you know, very minimal amount of calories. I'd much rather put the weight on. A lot better mood. It has to be better. It looks great. Everybody, chris hemsworth is here. Seriously great. "Thor: The dark world" opens nationwide on friday. Sam, I would say, I drew the long straw today. And not only that, but I knew it was november 8th because he has the biggest billboard in times square, right there. Turn around and show that giant billboard that says "thor." Real quick, sam. Chris, what is itike to see yourself three stories tall in times square? It's incredibly change. Never gets old. That's how I knew all about

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